ALSA: hda: Add snd_hdac_ext_bus_link_at() helper

This patch exposes a new helper to directly retrieve the link from the
codec address, and makes use of this helper when retrieving the link
from the codec name.
Signed-off-by: Cezary Rojewski <cezary.rojewski@intel.com>
Link: https://lore.kernel.org/r/20220214101404.4074026-2-cezary.rojewski@intel.comSigned-off-by: Takashi Iwai <tiwai@suse.de>

include/sound/hdaudio_ext.h

@@ -28,6 +28,7 @@ void snd_hdac_ext_stream_spbcap_enable(struct hdac_bus *chip,
 				 bool enable, int index);
 
 int snd_hdac_ext_bus_get_ml_capabilities(struct hdac_bus *bus);
+struct hdac_ext_link *snd_hdac_ext_bus_link_at(struct hdac_bus *bus, int addr);
 struct hdac_ext_link *snd_hdac_ext_bus_get_link(struct hdac_bus *bus,
 						const char *codec_name);
 

sound/hda/ext/hdac_ext_controller.c

@@ -132,6 +132,26 @@ void snd_hdac_link_free_all(struct hdac_bus *bus)
 }
 EXPORT_SYMBOL_GPL(snd_hdac_link_free_all);
 
+/**
+ * snd_hdac_ext_bus_link_at - get link at specified address
+ * @bus: link's parent bus device
+ * @addr: codec device address
+ *
+ * Returns link object or NULL if matching link is not found.
+ */
+struct hdac_ext_link *snd_hdac_ext_bus_link_at(struct hdac_bus *bus, int addr)
+{
+	struct hdac_ext_link *hlink;
+	int i;
+
+	list_for_each_entry(hlink, &bus->hlink_list, list)
+		for (i = 0; i < HDA_MAX_CODECS; i++)
+			if (hlink->lsdiid & (0x1 << addr))
+				return hlink;
+	return NULL;
+}
+EXPORT_SYMBOL_GPL(snd_hdac_ext_bus_link_at);
+
 /**
  * snd_hdac_ext_bus_get_link - get link based on codec name
  * @bus: the pointer to HDAC bus object
@@ -140,8 +160,6 @@ EXPORT_SYMBOL_GPL(snd_hdac_link_free_all);
 struct hdac_ext_link *snd_hdac_ext_bus_get_link(struct hdac_bus *bus,
 						 const char *codec_name)
 {
-	int i;
-	struct hdac_ext_link *hlink = NULL;
 	int bus_idx, addr;
 
 	if (sscanf(codec_name, "ehdaudio%dD%d", &bus_idx, &addr) != 2)
@@ -151,14 +169,7 @@ struct hdac_ext_link *snd_hdac_ext_bus_get_link(struct hdac_bus *bus,
 	if (addr < 0 || addr > 31)
 		return NULL;
 
-	list_for_each_entry(hlink, &bus->hlink_list, list) {
-		for (i = 0; i < HDA_MAX_CODECS; i++) {
-			if (hlink->lsdiid & (0x1 << addr))
-				return hlink;
-		}
-	}
-
-	return NULL;
+	return snd_hdac_ext_bus_link_at(bus, addr);
 }
 EXPORT_SYMBOL_GPL(snd_hdac_ext_bus_get_link);